The History Of Herodotus Volume 1 of 2
Page: 189151. Dareios being informed of this and having gathered together all his power, made expedition against them, and when he had marched his army up to Babylon he began to besiege them; but they cared nothing about the siege, for the Babylonians used to go up to the battlements of the wall and show contempt of Dareios and of his army by gestures and by words; and one of them uttered this saying: "Why, O Persians, do ye remain sitting here, and not depart? For then only shall ye capture us, when mules shall bring forth young." This was said by one of the Babylonians, not supposing that a mule would ever bring forth young.
152. So when a year and seven months had now passed by, Dareios began to be vexed and his whole army with him, not being able to conquer the Babylonians. And yet Dareios had used against them every kind of device and every possible means, but not even so could he conquer them, though besides other devices he had attempted it by that also with which Cyrus conquered them; but the Babylonians were terribly on their guard and he was not able to conquer them.
153. Then in the twentieth month there happened to Zopyros the son of that Megabyzos who had been of the seven men who slew the Magian, to this Zopyros, I say, son of Megabyzos there happened a prodigy,—one of the mules which served as bearers of provisions for him produced young: and when this was reported to him, and Zopyros had himself seen the foal, because he did not believe the report, he charged those who had seen it not to tell that which had happened to any one, and he considered with himself what to do. And having regard to the words spoken by the Babylonian, who had said at first that when mules should produce young, then the wall would be taken, having regard (I say) to this ominous saying, it seemed to Zopyros that Babylon could be taken: for he thought that both the man had spoken and his mule had produced young by divine dispensation.
154. Since then it seemed to him that it was now fated that Babylon should be captured, he went to Dareios and inquired of him whether he thought it a matter of very great moment to conquer Babylon; and hearing in answer that he thought it of great consequence, he considered again how he might be the man to take it and how the work might be his own: for among the Persians benefits are accounted worthy of a very high degree of honour. 132 He considered accordingly that he was not able to make conquest of it by any other means, but only if he should maltreat himself and desert to their side. So, making light esteem of himself, he maltreated his own body in a manner which could not be cured; for he cut off his nose and his ears, and shaved his hair round in an unseemly way, and scourged himself, and so went into the presence of Dareios.